Cost Effectiveness of Systemic Treatment Intensification for Metastatic Hormone-sensitive Prostate Cancer: Is Triplet Therapy Cost Effective?

Background and objective: There has been a shift toward systemic treatment intensification for men with metastatic hormone-sensitive prostate cancer (mHSPC). Recent trials have demonstrated the efficacy of triplet therapy with an androgen receptor signalling inhibitor (ARSI), docetaxel, and androgen deprivation therapy (ADT). However, ARSI treatment is expensive. The objective was to determine the cost effectiveness of current treatments strategies for men with mHSPC. Methods: We developed a Markov state-transition model to simulate outcomes for men with newly diagnosed mHSPC. For the simulation, patients were entered in the model in the mHSPC disease state before progressing to castration-resistant disease and finally dying from prostate cancer. Costs were calculated from a USA health sector perspective in 2022 US dollars. Deterministic and probabilistic sensitivity analyses were conducted to account for uncertainty in the parameter estimates. We also performed scenario analyses for costs in the UK and Australian health sectors. Key findings and limitations: Treatment intensification with doublet and triplet therapy resulted in an improvement in quality-adjusted survival for all strategies in comparison to ADT monotherapy. However, only docetaxel doublet therapy was cost effective at standard thresholds, with an incremental cost-effectiveness ratio of $13 647. The cost of ARSIs needed to be discounted by 47-70% before they were cost effective. Only medication costs impacted the model results. If the generic price for abiraterone acetate is used, then triplet therapy with abiraterone is the best-value option. Similar results were obtained for analyses for the UK and Australian health sectors. Conclusions and clinical implications: Treatment intensification with ARSIs in men with mHSPC results in better quality-adjusted survival but is not cost effective according to standard thresholds. The costs of these medications would need to be heavily discounted before they are cost effective. The cost of generic ARSIs, once available, would render these strategies cost effective. Patient summary: This report examines whether increasing the number of systemic drugs used to treat a patient's metastatic hormone-sensitive prostate cancer is cost